The Zelkova hollowed snare drum is CANOPUS' flagship model. In the primary development process we first experimented with traditional drum crafting theory.Originally we cut the drum's edge at an angle of 45 degrees on both the inside and outside of the drum's shell. Our first try was insufficient in resonance and was rather dull in regards to the drum's sensitivity.
We continued to experiment with several different edge angles. Including 70. 60 and 60 degrees. After our trials and errors. we have finally completed an unprecedented edge shaping process. The end result is a hand crafted snare drum with maximam resonance and a delicate yet fat sound with sharp response.(see figure)

Our new edge shaping is very sharp. This overturns existing edge shaping theory. What we learned through comprehensive. In order to pull the best potential sound out of the drum. the edge shaping must be determined by the material. thickness and structure of the shell. These lessons learned contributed to establish the framework for CANOPUS' development policy. These encounters have shaped our attitude towards the drum crafting process. Accordingly. when we are engaged in oour drums and accessory development project we doubt the widely accepted drum production theoly from the fundamental level.
Why are most snare drums made of plywood?

In order to pull out the best natural resonance. it is essential that the vibrating object must consist of a single element. In other words. a hollowed solid piece of wood is the ideal drum shell. When you compare the beating sound of a piece of solid wood to a piece of plywood the difference in sound quality is obvious.
A one piece snare drums is very fragile due to its struction. To cover up these shortcomings plywood shells are widely utilized. By plying several pieces of wood together with glue the drum shell is several more times durable than a one-piece shell. Consequently. natural resonance is therefore impaired in exchange for durability.

Throughout the world drum manufacturers have tried several approaches to combat the issue of a single element and durability. A block method is one approach and is closer to a one-piece shell. Another approach is to place a reinforcement hoop inside the bent piece of wood. One-piece wood is the most ideal in terms of pulling out the intrinsic natural resonance. Because of technical problems such as shell alteration and cracking. which may occur several years after the drums production. only a few manufacturers are producing hollowed one-piece wood snare drums.
Why Is A Hollowed One-Piece Snare Drum Subject To Crack?
The cylindrical shape of a one-piece snare drum is inevitably fragile. Therefore. we have adapted a new method. We have found the answer in "vector". When the force "FN"is given vertically against a curved surface. it branches off into f1. f2. and f3. The force f1 and f2 run along straight forward. while f3 runs through the curved surface. thereby causing a crack. (See FIG1) However. our original global shaped snare drum shell will disperse the given vertical force along the global surface. (See FIG2) Hence. we have achieved the desired outcome : a hollowed one-piece snare drum that is much stronger and more durable than the existing cylindrical surface of the present one-piece snare drums available. We have spent three years for the woods natural seasoning and also have the drum in a specially designed wood drier to reduce the moisture content down to 9 percent. This drying procedure contributes to minimize the shrinkage and cracking of the drum shell.
The Sound of Hollowed One-Piece Snare Drum Compared To a Plywood Snare Drum :

A hollowed one-piece snare drum has a distinctive fat strong sound. with good sound projection and a sharp response. Its tuning range is much wider than that of a plywood snare drum. These characteristics are major reasons why top drummers provide worldwide support to CANOPUS' Zelkova snare drum.
We do not put any grommets in the air hole of Zelkova snare drums for the following reasons:
1. We would prefer not to put any kind of hardware on the Zelkova. but a snare drum needs hardware. Therefore. we eliminate any extraneous metal or wood to preserve the resonance of the drum. 2. The wood can shrink. causing the grommet to rattle. The shell expands and contracts in response to temperature and moisture. Canopus takes every precaution to minimize drum shell shrinkage. Even though we dry the Zelkova snare drum shell until the moisture content is at 9% and the Zelkova snare drums shell is made without a seam (it's made from one. non-comprised piece of wood). there is a possibility that the shell could still shirink or expand due to the changes in air moisture. 3. Just look inside the air hole and you can appreciate the thickness of the single piece of wood.
A new revolving height adjustable tubular lug :

Zelkova snare drum, the flagship model of Canopus which enjoys a tremendous support ever since its introduction has now unveiled a new revolving height adjustable tubular lug as a standard feature.
Zelkova snare drum is given a hollowed one piece drum shell which comes from a stump of precious 200 years old Zelkova wood. After 3 years wood seasoning and moisture content is regulated down to 9 percent in the specially designed wood drier before shipment. However, this drum shell is tend to be affected by the outside humidity, and repeats contraction and expansion. The diameter of the shell gets longer when the humidity is high, and shorter when humidity is low.
Since commonly used lug has swivel feature which takes in tension bolt, so It wouldn’t matter if the drum shell expands or contracts. However, tubular lug of Canopus has no swivel feature as it is solid structure in order to enhance vibration cycle efficiency.

Sometimes tubular lug may not be able to take in tension bolt when expansion and contraction occurs on the shell. A new revolving height adjustable tubular lug is designed in order to solve this problem. It has a mechanism which enables to make optional height adjustment at the interval of plus or minus 2mm by turning center pole of lug.